Various methods have been used for increasing the effective capacity and functionality of selective call radio communication systems, such as paging systems. Such methods transmit to the selective called devices, such as pagers, a short segment of information (herein called a token) which is substituted for a longer segment of information such as a caller source ID (phone number), a call back number, any one predetermined alphanumeric phrase, or any one digitized voice audio signal. One such method appends a token, which identifies the caller phone number, to an alphanumeric message of variable length and transmits the appended message to the pager. When the message is received by the pager, either the message is presented to the user with the tokens as received, or the long phrase is substituted back into the messages before the messages are further processed for presentation or other use. In the latter case, the tokens and associated long phrases must be stored into a memory within the pager, and a means of associating the long phrases with the tokens is required. In either case, the use of tokens reduces the transmission duration, thus increasing the effective capacity of the system. The tokens are typically digital in nature whereas the long phrases can be reconstructed voice.
A method of determining the long phrases that are stored in the pager has generally been by a review of transmitted message history performed by a person, using informal (undocumented) rules. A means of storing the selected long phrases and associated tokens in the pager memory is by connecting the pager to a programmer which can program the tokens and the long phrases. The long phrases and tokens may be programmed at the time of manufacture of the pager, or they may be stored or altered after manufacture.
In either case, the selection of the long phrases may be inappropriate for a user's needs and quickly outdated largely because of the difficulty of altering the long phrases in the pagers, and also due to the human effort required to select more appropriate phases. Furthermore, because of the prior art manual methods used to select the phrases, the long segments of information stored in the pagers tend to be the same for all pagers used in a system, or at least for all pagers in a large portion or the system.
The use of a one token appended to a selective call message does not provide nearly as much channel efficiency improvement when longer alphanumeric message are being used in a system. Under these circumstances, it is not productive to attempt to shorten entire messages to unique tokens because they tend to be all different. Even with a common phrase (such as telephone numbers or the phrase "Call me") shortened to tokens, the remaining text tends to be longer in newer systems which employ pagers with memories that encourage the use of long text messages.
Thus, what is needed is a means to improve the process of selecting the common long phrases within text messages, on a unit by unit basis, and an improved means of storing the long phrases and the associated tokens into the pagers.